Enhanced flotation balloon

ABSTRACT

The present invention provides a balloon fabricated from a metalized polymeric film having to allow the balloon when filled with helium to float for a period in excess of fifteen days.

CROSS-REFERENCE TO RELATED APPLICATION

Not applicable.

FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

BACKGROUND OF THE INVENTION TECHNICAL FIELD

The present invention provides an inflatable object such as a balloon capable of retaining a lighter-than-air gas such as helium and to float for a period in excess of twenty days.

BACKGROUND ART

Balloons, including lighter-than-air balloons, are well-known in the art. Lighter-than-air balloons are used for decorations at parties, given as gifts, and presented to persons with floral or other arrangements at special occasions such as graduations, birthdays, Valentine's Day, and Mothers' Day. Such balloons often bear indicia of the occasion, such as “Happy Birthday,” “Over the Hill,” or “Congratulations.”

Lighter-than-air balloons are typically filled with helium, but may be filled with any lighter-than-air gas. Thus, the balloons float in air. The balloons may be made from a variety of materials, including natural or synthetic rubber, polyester, metallized polyester, nylon, or metallized nylon. Commercially available balloons typically will float for less than ten to fifteen days after being filled. The helium barrier properties of the material from which the balloons are fabricated are insufficient to allow for fabrication of a balloon that will float beyond fifteen days. Accordingly, there is a need for an enhanced flotation balloon that will float for a period in excess of fifteen days.

DETAILED DESCRIPTION OF THE INVENTION

While this invention is susceptible of embodiment in many different forms, there is shown in the drawings, and will be described herein in detail, specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated.

The present invention provides a balloon when filled with a lighter-than-air gas can float for a period in excess of fifteen days, more preferably for twenty days and even more preferably for twenty-five days and beyond. The balloon is fabricated from a film having a multilayer structure. The multiple layer structures can include layers such as a seal layer, a decorative layer, a barrier layer for increasing the time for passage of helium across the film, tie layers, or other layers. The layers of the structure can include polymeric materials and metals. Suitable polymeric materials polyolefins, polyesters, polyamides, polyetheramides, polystyrene, styrene and hydrocarbon copolymers, ethylene vinyl alcohol (EVOH) and/or PVDC.

Suitable polyolefins include homopolymers, copolymers and terpolymers obtained using, at least in part, monomers selected from α-olefins having from 2 to 20 carbons. One particularly suitable polyolefin is an ethylene and α-olefin interpolymer (which sometimes shall be referred to as a copolymer). Suitable ethylene and α-olefin interpolymers preferably have a density, as measured by ASTM D-792 of less than about 0.915 g/cc and are commonly referred to as very low density polyethylene (VLDPE), ultra low density ethylene (ULDPE) and the like. The α-olefin should have from 3-17 carbons, more preferably from 4-12 and most preferably 4-8 carbons. In a preferred form of the invention, the ethylene and α-olefin copolymers are obtained using single site catalysts. Suitable single site catalyst systems, among others, are those disclosed in U.S. Pat. Nos. 5,783,638 and 5,272,236. Suitable ethylene and α-olefin copolymers include those sold by Dow Chemical Company under the AFFINITY tradename, Dupont-Dow under the ENGAGE tradename and Exxon under the EXACT and PLASTOMER tradenames.

The polyolefins also include modified polyolefins and modified olefins blended with unmodified olefins. Suitable modified polyolefins are typically polyethylene or polyethylene copolymers. The polyethylenes can be ULDPE, low density (LDPE), linear low density (LLDPE), medium density polyethylene (MDPE), and high density polyethylenes (HDPE). The modified polyethylenes may have a density from 0.850-0.95 g/cc. The polyethylene may be modified by grafting or otherwise chemically, electronically or physically associating a group of carboxylic acids, and carboxylic acid anhydrides. Suitable modifying groups include, for example, maleic acid, fumaric acid, itaconic acid, citraconic acid, allylsuccinic acid, cyclohex-4-ene-1,2-dicarboxylic acid, 4-methylcyclohex-4-ene-1,2-dicarboxylic acid, bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid, x-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid, maleic anhydride, itaconic anhydride, citraconic anhyride, allylsuccinic anhydride, citraconic anhydride, allylsuccinic anhydride, cyclohex-4-ene-1,2-dicarboxylic anhydride, 4-methylcyclohex-4-ene-1,2-dicarboxylic anhydride, bicyclo[2.2.1]hept-5-ene2,3-dicarboxylic anhydride, and x-methylbicyclo[2.2.1]hept-5-ene-2,2-dicarboxylic anhydride.

Examples of other modifying groups include C₁-C₈ alkyl esters or glycidyl ester derivatives of unsaturated carboxylic acids such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, glycidyl acrylate, glycidal methacrylate, monoethyl maleate, diethyl maleate, monomethyl maleate, diethyl maleate, monomethyl fumarate, dimethyl fumarate, monomethyl itaconate, and diethylitaconate; amide derivatives of unsaturated carboxylic acids such as acrylamide, methacrylamide, maleicmonoamide, maleic diamide, maleic N-monoethylamide, maleic N,N-dietylamide, maleic N-monobutylamide, maleic N,N dibutylamide, fumaric monoamide, fumaric diamide, fumaric N-monoethylamide, fumaric N,N-diethylamide, fumaric N-monobutylamide and fumaric N,N-dibutylamide; imide derivatives of unsaturated carboxylic acids such as maleimide, N-butymaleimide and N-phenylmaleimide; and metal salts of unsaturated carboxylic acids such as sodium acrylate, sodium methacrylate, potassium acrylate and potassium methacrylate. More preferably, the polyolefin is modified by a fused ring carboxylic anhydride and most preferably a maleic anhydride.

The polyolefins also include ethylene vinyl acetate copolymers, modified ethylene vinyl acetate copolymers and blends thereof. The modified EVA has an associated modifying group selected from the above listed modifying groups. Other suitable polyolefins include copolymers of ethylene such as ethylene and lower alkyl acrylate copolymers, and ethylene and lower alkyl substituted alkyl acrylate copolymers.

Suitable polybutadienes include the 1,2- and 1,4-addition products of 1,3-butadiene (these shall collectively be referred to as polybutadienes). In a more preferred form of the invention, the polymer is a 1,2-addition product of 1,3 butadiene (these shall be referred to as 1,2 polybutadienes). In an even more preferred form of the invention, the polymer of interest is a syndiotactic 1,2-polybutadiene and even more preferably a low crystallinity, syndiotactic 1,2 polybutadiene. In a preferred form of the invention, the low crystallinity, syndiotactic 1,2 polybutadiene will have a crystallinity less than 50%, more preferably less than about 45%, even more preferably less than about 40%, even more preferably the crystallinity will be from about 13% to about 40%, and most preferably from about 15% to about 30%. In a preferred form of the invention, the low crystallinity, syndiotactic 1,2 polybutadiene will have a melting point temperature measured in accordance with ASTM D 3418 from about 70.degree. C. to about 120.degree. C. Suitable resins include those sold by JSR (Japan Synthetic Rubber) under the grade designations: JSR RB 810, JSR RB 820, and JSR RB 830.

Acceptable polyamides also include aliphatic polyamides resulting from the condensation reaction of di-amines having a carbon number within a range of 2-13, aliphatic polyamides resulting from a condensation reaction of di-acids having a carbon number within a range of 2-13, polyamides resulting from the condensation reaction of dimer fatty acids, and amide containing copolymers. Thus, suitable aliphatic polyamides include, for example, nylon 66, nylon 6,10 and dimer fatty acid polyamides.

Suitable polyesters include polycondensation products of di- or polycarboxylic acids and di or poly hydroxy alcohols or alkylene oxides. Preferably, the polyesters are a condensation product of ethylene glycol and a saturated carboxylic acid such as ortho or isophthalic acids and adipic acid. More preferably the polyesters include polyethyleneterphthalates produced by condensation of ethylene glycol and terephthalic acid; polybutyleneterephthalates produced by a condensations of 1,4-butanediol and terephthalic acid; and polyethyleneterephthalate copolymers and polybutyleneterephthalate copolymers which have a third component of an acid component such as phthalic acid, isophthalic acid, sebacic acid, adipic acid, azelaic acid, glutaric acid, succinic acid, oxalic acid, etc.; and a diol component such as 1,4-cyclohexanedimethanol, diethyleneglycol, propyleneglycol, etc. and blended mixtures thereof. In a preferred form of the invention the polyesters will be selected from those sold BY DuPont under the tradename MYLAR, POLYMEX, POLYMEX OPP, MELINEX, HOSTAPHAN, LUMIRROR, CLARYL AND EXCELL.

Suitable polyesters also include polyester ethers obtained from reacting 1,4 cyclohexane dimethanol, 1,4 cyclohexane dicarboxylic acid and polytetramethylene glycol ether and shall be referred to generally as PCCE. Suitable PCCE's are sold by Eastman under the trade name ECDEL. Suitable polyesters further include polyester elastomers which are block copolymers of a hard crystalline segment of polybutylene terephthalate and a second segment of a soft (amorphous) polyether glycols. Such polyester elastomers are sold by DuPont Chemical Company under the trade name HYTREL.

Suitable styrene and hydrocarbon copolymers include styrene and the various substituted styrenes including alkyl substituted styrene and halogen substituted styrene. The alkyl group can contain from 1 to about 6 carbon atoms. Specific examples of substituted styrenes include alpha-methylstyrene, beta-methylstyrene, vinyltoluene, 3-methylstyrene, 4-methylstyrene, 4-isopropylstyrene, 2,4-dimethylstyrene, o-chlorostyrene, p-chlorostyrene, o-bromostyrene, 2-chloro-4-methylstyren- e, etc. Styrene is the most preferred.

The hydrocarbon portion of the styrene and hydrocarbon copolymer includes conjugated dienes. Conjugated dienes which may be utilized are those containing from 4 to about 10 carbon atoms and more generally, from 4 to 6 carbon atoms. Examples include 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, chloroprene, 1,3-pentadiene, 1,3-hexadiene, etc. Mixtures of these conjugated dienes also may be used such as mixtures of butadiene and isoprene. The preferred conjugated dienes are isoprene and 1,3-butadiene.

The styrene and hydrocarbon copolymers can be block copolymers including di-block, tri-block, multi-block, star block and mixtures of the same. Specific examples of diblock copolymers include styrene-butadiene, styrene-isoprene, and the hydrogenated derivatives thereof. Examples of triblock polymers include styrene-butadiene-styrene, styrene-isoprene-styrene, alpha-methylstyrene-butadiene-alpha-methylstyre-ne, and alpha-methylstyrene-isoprene-alpha-methylstyrene and hydrogenated derivatives thereof.

The polymeric portion of the film can be fabricated by lamination, extrusion lamination, coextrusion, molding, blow molding, blown extrusion or other suitable polymer processing technique well known in the art. A single layer of the film or the polymeric portion of the film can be subjected to processing techniques such as monoaxial orientation, biaxial orientation, heat treatment, corona discharge or the like.

The polymeric portion of the film is preferably subjected to a metallization procedure to place a metal layer on a single side of the polymeric portion to form an outer layer or can be included on both sides of the polymeric structure to sandwich the polymeric structure between the metal layers. If both sides of the film are metalized a portion of the metal along a periphery of what will be the balloon, in a preferred form, will be stripped away to expose a portion of the polymeric portion of the film to form a seal layer.

In a preferred form of the invention the balloon material is a metalized polyester or a metalized nylon and most preferably a metalized poly(ethylene terephthalate) (PET). In a more preferred form of the invention the film is that developed by Toray on behalf of the Applicant and designated as MK11.

From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. It is, of course, intended to cover by the appended claims all such modifications as fall within the scope of the claims. 

1. A balloon comprising: a sidewall fabricated from a metalized polymeric film; the film having sufficient barrier properties to the passage of helium to allow the balloon when filled with helium to float for a period in excess of fifteen days.
 2. The balloon of claim 1 wherein the period is for twenty days.
 3. The balloon of claim 1 wherein the period is for twenty five days.
 4. The balloon of claim 1 wherein the period is for thirty days. 